Discover Where American Express Is Accepted -
Differences Between Visa, Mastercard, and American Express Visa and Mastercard are only payment networks. The companies do not provide cards but help in managing transactions between shops and banks. However, American Express is both a payment network and a card issuer. The company issues its own cards and manages the transactions being made. Visa cards are said to be the most popular cards in the world and the largest payment network in the United States....